This paper presents our preliminary experimental results on the encountered many problems when producing urban true orthoimages of downtown, where a number of high buildings present. These problems, mainly including building occlusions, street visibility, shadows, incomplete refilling, digital surface model, quality of source images, and the existing orthorectification models, may be common to true orthoimage generation in other areas with similar conditions. These problems along with our analysis to them are presented with details in the paper. Based on the analysis, this paper also proposes some possible solutions to minimize the effects of these problems on the final true orthoimage outputs.
Guoqing Zhou, Zhihao Qin, Susan Benjamin, J. Rand,